356 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 34 



Pollux, who wrote in the second century. His terminology includes 

 both the kingbolt and the wheel plate, or rubbing strip. 



ROMAN RULP: of THE ROAD A MOOT QUESTION 



The question as to whether the traffic on the Roman roads passed 

 to the right or left of an oncoming vehicle is difficult to answer with 

 certainty. The evidence, however, seems to indicate that the preva- 

 lence of the box wagon or postilion method of driving established the 

 rule of the road in any given locality. In the country districts, 

 where the box wagon was in general use, the practice was for the 

 driver to sit on the extreme right side of the seat in order to permit 

 the free play of his right whip hand. Thus he passed to the left so 

 as to gage more accurately the clearance between the wheel hubs of 

 his own and the approaching vehicle. In the city districts, however, 

 where the postilion rode upon the left wheel, or rear horse, so as to 

 permit the most direct use of the right whip hand, it was the custom 

 to pass oncoming vehicles to the right. 



When Premier Mussolini came into power, the rural traffic in Italy 

 passed to the left, while the urban custom was to pass to the right. 

 This difference in custom was abolished by an edict of the Premier 

 which made the right-hand rule of the road mandatory everywhere. 



In North America, in the Colonial days, although there was no 

 generally accepted rule, the prevailing practice was to pass to the 

 left in accordance with the English custom. The advent of the heavy 

 Conestoga covered freight wagons in Pennsylvania, about the year 

 1750, with their postilion method of driving, began the establishment 

 of the right-hand rule of the road, which is now universally observed 

 in the United States. 



DISTINGUISHING CHARACTERISTICS OF THE ROMAN ROADS 



Although undaunted by natural obstacles and great differences in 

 elevation, the Romans took advantage of all natural conditions in 

 order to make the most of the engineering knowledge of their times. 

 They avoided cuts wherever possible, because of inadequate excavat- 

 ing equipment, and they preferred sidehill location to the exclusion 

 of valleys where the foundation problems were more difficult. 



No attempt was made to balance cuts and fills either in profile or 

 cross-section. Except for sidehill excavation, open cuts are usually 

 found only in rock. Since no explosives were available at that time 

 and solid rock was removed by the slow and laborious process of 

 wedging and picking, one can readily appreciate their aversion to 

 solid rock excavation. Where rock work was necessary the Romans 

 preferred tunnels to through cuts in order to confine the hand labor 



